A conventional drum type washing machine is shown in FIG. 3 (see, for example, Japanese Patent Laid-Open Application No. 2004-195100). Hereinafter, a configuration thereof will be described.
As shown in FIG. 3, rotary drum 1 provided with multiple drum perforations 2 in its cylindrical surface is rotatably installed in water tub 5 supported by suspension structure 4 within housing 3. Rotary drum 1 is also provided with rotating shaft (central shaft of rotation) 6 at its center of rotation and is disposed such that rotating shaft 6 is upwardly inclined toward the front portion of the washing machine. Motor 7 is connected to rotating shaft 6 to make rotary drum 1 rotate. Further, a number of agitation blades 8 are disposed on the inner cylindrical surface of rotary drum 1.
Further, by opening door 9, which is installed at the front portion of housing 3 such that it can be freely opened and closed, laundry can be loaded into or unloaded from rotary drum 1 via housing opening 3a, water tub opening 5a and rotary drum opening 1a formed at housing 3, water tub 5 and rotary drum 1, respectively.
Moreover, respective centers of housing opening 3a, water tub opening 5a and rotary drum opening 1a are arranged such that they lie on a substantially same line, namely, on a central axis of rotation of rotating shaft 6. Further, respective inclination angles of housing opening 3a, water tub opening 5a and rotary drum opening 1a with respect to a vertical plane are set to be virtually identical.
When the operation of the drum type washing machine is initiated after laundry being loaded into rotary drum 1 through opening door 9 and detergent being added thereto, a predetermined amount of water is supplied in water tub 5 via water supply valve 10 and a portion thereof flows into rotary drum 1 through drum perforations 2 as well. Then, when rotary drum 1 is driven to rotate at a predetermined rotational speed by motor 7, the laundry in rotary drum 1 is lifted up in the rotational direction by agitation blades 8 disposed on the inner cylindrical surface of rotary drum 1 and drops down upon reaching a specific height, thereby undergoing pounding motions to be washed. After completion of the washing process, soiled wash water is drained via water drain valve 11, and a rinsing process is carried out in fresh water. Then, when the rinsing process is finished, a water-extracting process for spinning rotary drum 1 at a high rotational speed is executed. The series of processes described are automatically performed in accordance with a preset control sequence stored in controller 12.
With the above-described configuration, user can easily see the inside of rotary drum 1 from above in the drum type washing machine in comparison with a drum type washing machine with a housing opening, a water tub opening and a rotary drum opening provided in a vertical direction. Further, loading and unloading of the laundry into and from rotary drum 1 can be performed more conveniently.
Since housing opening 3a, water tub opening 5a and rotary drum opening 1a are arranged concentrically to thereby have respective centers thereof substantially on the central axis of rotation of rotary drum 1 and the respective inclination angles of housing opening 3a, water tub opening 5a and rotary drum opening 1a with respect to the vertical plane are set to be substantially same, there is a blind spot in the front portion of rotary drum 1, i.e., a space that cannot be directly observed, when door 9 is opened. Therefore, a user may fail to spot any laundry in the space, thereby failing to pick up the laundry. Further, in order to ameliorate the inconvenience of the user having to bend down a lot to load and unload laundry into and out of rotary drum 1, the housing opening 3a's angle of inclination needs to be set large. To this end, it is required that a depth dimension of housing 3 becomes increased, but there is a limit thereto as well. For this reason, the size of the angle of inclination of housing opening 3a should be limited within a specific range to be accommodated within the limited depth dimension of housing 3.